Bioaccumulation of heavy metals in Spartina

The Spartina Schreb. genus is composed of C4 perennial grasses in the family Poaceae. They are native to the coasts of the Atlantic Ocean in western and southern Europe, north-west and southern Africa, the Americas and the southern Atlantic Ocean islands. Most species are salt tolerant and colonise coastal or inland saltmarshes. The available literature on heavy metal bioaccumulation by Spartina sp. was compiled and compared. Spartina alterniflora Loisel. and Spartina maritima (Curtis) Fernald were the most commonly researched species of the genus, whereas many species were not represented at all. In contrast, Cu and Zn are the most intensively researched heavy metals. The few studies dealing with the physiological impacts of heavy metals or the mechanisms of metal accumulation, which involve extracellular and intracellular metal chelation, precipitation, compartmentalisation and translocation in the vascular system, were documented. Bioaccumulation of metals in roots and tillers of some species of the Spartina genus (e.g. S. maritima and Spartina densiflora Brongn.) has been described as a feasible method for remediating waters and soils contaminated with heavy metals. One such example is Spartina argentinensis Parodi, which has been found to be a Cr-hyperaccumulator; it can concentrate chromium in its tissues to levels far exceeding those present in the soil.